Slack adjuster



Feb- 22 1927"' w. H. SAUVAGE SLACK ADJUSTER Filed Feb. 9. 1925 Patented Feb. 22, 1927.

UNITED STATES l .l 1,618,783 PATENT oFFlca.

WILLIAM H. SAUVAGE, F NEW YORK, N. Y., ASSIGNOR, IiBY MESNE ASSIGNMENTS, TO

GOULD COUPLER COMPANY, O F NEW YORK, N. Y. l

SLACK ADJUSTER.

Application led February 9, 1925. Serial No. 7,956.

This invention relates to slack adjustersl automatic slack adjusters for brake rigging of railway cars or the like.

One of the objects of the present invention is to provide a reliable and etlicient slack adjuster of the above character par ticularly adapted to co-act with the truck brake rigging of railway cars, although it will, of course, be understood that various features thereof are applicable to other in.- stallations without material modification.

A. further object is to provide a slack adjuster of simple and practical construction adapted to take up all yof the excess travel of the brake rigging upon each complete actuation of the brakes.

A further object is to provide a slack adjuster particularly adapted to'be mounted upon the underside of the car body and oper-1 able to take u the slack in the brake rigging ofthe a jacent truck, yet permitting free movement of the truck with respect to the car body, without actuation of the slack adjuster mechanism as when the car makes a turn. Y v

Other objects will be in part obvious from the annexed drawings and in part indicated in connection therewith by the following analysis of this invention.

The invention accordingly consists in the features of construction, combination of parts and in the unique relations of the various members and in the relative proportioning and disposition thereof, all as more completely outlined herein.

To enable others skilled in the art so fully to comprehend the underlying features thereof that they may embody the same by numerous modifications in structure and relation contemplated by this invention, a drawing depicting a preferred form has been annexed as a part of this disclosure, and in such drawing like characters of reference denote corresponding .parts throughout.

In the drawing, there is shown in elevation such parts of the slack adjusterhcar body, truck and associated brake mechanism, certain parts thereof being broken away for sake of convenience, asis necessary to understand the invention.

Referring now to the drawings, 5 indicates a truck bolster pivotally mounted in a well .known manner on the underside of the car body provided with the usual draft sill 6. At each side of the bolster are posi-` tloned brake actuating levers comprising a dead lever 7 and a live lever 8, connected by bottom rod 10, the upper end of the live lever being provided with the usual pull rod 11 and the upper end of the dead lever being connected by link 12 with the slack adjuster mechanism hereinafter described. It will also be noted that a second link 13 extends from the slack adjuster mechanism to the pull rod 11, provided at its end with an eye 14 through which the null rod passes. A friction clamp 14a is mounted on the pull rod, and normally spaced to the left of the eye 14 an amount equal to the usual piston travel. Thus, as the upper end of the live lever is moved an excess amount toward the right by the pull rod 11, the connecting rod or link 13 will have a corresponding movement on excess travel thereof. The truck brake mechanism herein shown is of such ge'neral and well known type and operation that further description thereof is believed to be unnecessary.

The slack adjuster as herein shown and described comprises a casing 15 referably formed of two halves adapted to be secured together in any desired manner, as by means of fastening devices 16, and secured to the car body or draft sill by any desired supporting means, such as the bracket 17. rlhis slack adjuster is provided with an adjusting rod 18 connected at one end with the link 13 and having-at its opposite end -a pawl 20 vprovided with an upwardly eX- tending lug 21 normally engaging the top of the housing 15 in such manner as to be held out of engagement with the teeth of a Vrack 22 on the upper surface of a permanent take up means or bar 23. A s iral spring 24 is coiled about the rod 18 to old the parts in normal position. The upper surface of the housing 15 is provided with a recessed portion 25 of perhapssix or seven inches in lengt-h, which begins approximately three or four inches from the end of the projecting lug 21. This three-inch or more space may be considered a lost motion provision for permitting the normal actuation of the brakes.

A second pawl 27 mounted in the casing 15 isresiliently urged into engagement with rack 22 by means of a spring 28 positioned in a housing 30, which mechanism acts to permanently take up and hold the excess slack occurring upon each application of the brakes.

The operation of the device 'so far de scribed is as follows: As the pull rod 11 moves toward the right in the usual brakine' operation, it will cause the link 13 and rod 18 to move a. corresponding distance and carry the pawl 20 therewith through the usual lost motion space, and the parts, upon release of the brakes, will be carried back to their original position. lf, however', due to wear of the parts as brake shoes, the actuating rod 11 exceeds this predetermined travel, the end 21 of the pawl 2O then moves up the inclined end of 'the recessed portion 25 allowing the pawl to drop into engage ment with the rack 22. As is well known to those familiar with railway brakes, the usual piston travel or actuating movement is usually set for six on seven inches. Thus, after 'the pawl 2O moves into engagement with the rack 22 Aat the end of lost motion movement, correspondingr to the usual piston travel, the pull rod 11 moves still further due to wear of the brake shoes, for example, to secure complete braking operation. Under these conditions, the pawl 20 will have engaged the rack, the end 21 being at the top of the inclined portion of the enlargement 25. As soon, however, as the brakes are released the spring 24, which, in the meantime is under high compression, will cause a return movement of the adjusting Yrod 18 towards the left which carries with it for the distance of the excess travel, and through the medium of the cam 20 and rack 24, the take up rod 23. The pawl 27, during -thls movement of the rod 23 to the left, rides over the teeth 22 while the excess travel is being taken up. Further movement, however, causes the end 21 of paw] 20 to engage the inclined surface of the recess 25 to disengage the pawl 20 from the rack, the awl 27 permanently holding the excess sack. Thus, if elvcess travel occurs and the adjusting rod moves seven inches instead of 'the normal six inches, the pawl 20 rides over an additional tooth and on release of the brakes and on expansion of the spring 24, the adjusting rod 23 will be moved towards the left the distance of one toth before the camming action above described 'takes place. The spring being under a high degree of compression. will thus positively insure the taking up of the slack adjuster on each complete cycle of operation.

It will be noted that the rod 23 is provided with a downwardly extended weighted handie 31 which not only maintains the rack in up ermost position, but permits the rod 23 to lie turned through 90, thus forcing the pawl 27 out of engagement with the rack 22 and allowing the rod i23 to be moved inwardly to its initial position. This operation is necessary, as when replacing worn brake shoes, or the like.

It is believed to be unnecessary to further state the operation of this device in view-of the above. Particular attention, however, is directed 'to the special type of ratchet and take up dog which is normally out of engagement with the rack bar until excess travel occurs, when it effectively engages with an additional tooth of the rack bar `to the extent of this excess travel. Under" these conditions, the take up spring 24 is .under a severe compression, so that if only one or more teeth have been taken up, due to eX- cess travel, the spring has stored sulicient drivingr force to positively insure a prompt and ellicient t-ake up of this excess slack or travel.

The invention is of simple and practical construction, and highly reliable in use and operation, and is well adapted to accomplish among others all of the objects und advantages herein set forth.

"Without further analysis the foregoing will so fully1 reveal the gist of this invention and others can by applying current knowledge readily adapt it for various applications without omitting certain features that, from the standpoint of the prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention, and, therefore, such adaptations should and are intended to be com rehended within the meaning and range o equivalency of the following claims.

I claim:

l. In an apparatus of the character described, in combination with the truck brake rigging of a railway car, a slack adjuster secured to the car body and connected .with the actuating member of the truck rigging, comprising a rack, a permanent take up and holding means, a temporary take up and holding means normally spaced from the rack, and a spring adapted to be actuated on each operation of the brakes, said temporary take up means being operative only on excess travel of the brake rigging.

2. In an apparatus of the character described, in combination with the truck brake rigging of a railway car, a slack adjuster associated therewith, comprising an adjusting rod actuated upon each operation of the brakes. a permanent take up rod, a ratchet thereon, a pawl on the adjusting rod normally out of engagement with said ratchet but cooperative therewith ou excess travel to move the take up rod, andmeans for holding the take up rod in its newly adjusted position.

3. In an apparatus of the character described, in combination with the truck brake rigging of a railway car, a. slack adjuster mounted upon `the car, an adjusting rod connected with the. actuating mechanism o f the brake rigging, a take up rod having a rack, a pawl carried by the ad'usting rod adapted to engage the said rac ron release of the brakes only if excess travel has occurred, and means for holding said rack in its newly adjusted position.

4. In an ap aratus of the character described, in com` ination with the truck brake rigging of a railway car, a Slack adjuster mounted upon the car, an adjusting rod connected with the actuating mechanism of the brake rigging, a take up rod having a rack, a pawl carried by the adjusting rod adapted to engage the saidrack on release of the brakes only if excess travel has occurred, and means for holding said rack in its newly adjusted position, said means coniprising 'z'pawl cooperating with said rack, and means for urging said pawl into engagement therewith ,at all times.

5. In an apparatus of the' character described, in combination with the truck brake rigging of a railwa car, a slack adjuster mounted on the un erside of the car, and connected to both the live and dead levers of the brake rigging, one of said connections including permanent take up and holding means, the other of said connections` including temporary take up mechanism, a rack scribed, in com ination with the truck brake rigging of al railway car, a slack adjuster mounted on the underside oi" the car, and

connected to both the live and dead levers of the brake rigging, one of said connections includin permanent take up and holding means, t e other of said connections including temporary take up mechanism, a rack mounted on the former, and two pawlsone of which is normall out of engagement with the rack and a pted to co-act therewith at each operation of the brakes but to move the rack only on excess travel, the.

other of Asaid. pawls being normall urged into engagement with the rack at al times, and means whereby said rack may be rotated to carry' the pawl out of engagement therewith. l

Signed at New York city this 8th day of January, 1925.

' WILLIAM H. SAUVAGE. 

